In reply to carl1:
We did in 2008, it was pretty old kit (Silvretta 505 bindings) and the sledges we hired would have embarassed a toddler in the park. I can't quite remember the details, but the guide was called Merlin and I think it was John Biggar (
http://www.andes.org.uk/) who put us on to him.
Take some playing cards, we spent a few days digging the tent our of snow drifts and pissing in a spare pan on the ice cap. It made for a memorable honeymoon.